/*
 * OREKIT-X
 * Copyright 2002-2008 CS Communication & Systemes
 * 
 * Parts of this software package have been licensed to CS
 * Communication & Systemes (CS) under one or more contributor license
 * agreements.  See the NOTICE file distributed with this work for
 * additional information.
 *  
 * This is an experimental copy of OREKIT from www.orekit.org.
 * Please use the original OREKIT from orekit.org for normal work
 * unrelated to this research project.
 * 
 * Licensed under the Apache License, Version 2.0 (the "License"); you
 * may not use this file except in compliance with the License.  You
 * may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
 * implied.  See the License for the specific language governing
 * permissions and limitations under the License.
 */
package ore.frames;

import ore.errors.OrekitException;
import ore.time.AbsoluteDate;

/** 
 * Earth Orientation Parameters IAU2000
 * 
 * @author Pascal Parraud
 */
public class EOP2000History
    extends EOPHistory
{

    private static final String EOPC04FILENAME = "^eopc04_IAU2000\\.(\\d\\d)$";
    private static final String BULLETFILENAME = "^bulletinb_IAU2000((-\\d\\d\\d\\.txt)|(\\.\\d\\d\\d))$";


    public EOP2000History() throws OrekitException {
        super();

        new ore.io.EOP05C04FilesLoader(EOPC04FILENAME,this);
        new ore.io.BulletinBFilesLoader(BULLETFILENAME,this);
        this.checkEOPContinuity(Continuity);
        Instance = this;
    }

    /**
     * Get the UT1-UTC value.  The data provided comes from the IERS
     * files. It is smoothed data.
     * 
     * @param date date at which the value is desired
     * @return UT1-UTC in seconds (0 if date is outside covered range)
     */
    public double getUT1MinusUTC(final AbsoluteDate date) {

        return this.getInterpolatedField(date, EOP.Field.ut1utc);
    }
    /** 
     * Get the LoD (Length of Day) value.  
     * 
     * @param date Date at which the value is desired
     * @return LoD in seconds (0 if date is outside covered range)
     */
    public double getLOD(final AbsoluteDate date) {

        return this.getInterpolatedField(date, EOP.Field.lod);
    }
    /** 
     * Get the interpolated IERS Reference Pole correction.  
     * 
     * @param date Date at which the correction is desired
     * 
     * @return Pole correction, may be the {@link
     * PoleCorrection#NULL_CORRECTION} if date is outside covered
     * range
     */
    public PoleCorrection getPoleCorrection(final AbsoluteDate date) {

        return new PoleCorrection(this.getInterpolatedField(date, EOP.Field.poleX),
                                  this.getInterpolatedField(date, EOP.Field.poleY));
    }
}
